The present invention relates to the prevention of vibration in a vehicle hydraulic brake.
In a vehicle provided with a hydraulic brake, uneven thickness of the disc rotor, insufficient cylindricity of the brake drum, etc., may cause vibration of the car body or the steering system, and some times pulsatile movement of the brake pedal. These are generally called a brake vibration. Uneven thickness of the disc rotor, insufficient cylindricity or insufficient concentricity of the brake drum, etc., may retroactively cause, through the vibration of the brake pads or brake shoes which urge the disc or drum, periodical fluctuation of fluid pressure (hereinafter simply called fluid pressure vibration) in the relevant wheel cylinders. It consequently brings about a fluctuation of braking torque. Conventional efforts for preventing the brake vibration have been focused only on the enhancement of the precision in manufacturing of such parts as disc rotor or brake drum, or in assemblying of those, seeking a favorable construction thereof to avoid errors in fixing. Efforts and endeavors in this direction have resulted in rising of cost and in arriving at a practical limit of maching technology. This invention has been made from such a background.